Eager-load host and chapter-organiser chains for event listings

app/controllers/events_controller.rb

@@ -8,13 +8,15 @@ def index
   end
 
   def upcoming
-    fresh_when(latest_model_updated, etag: latest_model_updated)
+    latest = latest_model_updated
+    fresh_when(latest, etag: latest)
 
     @events, @pagy = fetch_upcoming_events
   end
 
   def past
-    fresh_when(latest_model_updated, etag: latest_model_updated)
+    latest = latest_model_updated
+    fresh_when(latest, etag: latest)
 
     @past_events, @pagy = fetch_past_events
   end
@@ -166,7 +168,9 @@ def load_events(rows)
       (hash[row['event_type']] ||= []) << row['id'].to_i
     end
 
-    workshops = Workshop.eager_load(:chapter, :sponsors, :organisers, :permissions, :workshop_host)
+    workshops = Workshop.eager_load(:sponsors, :organisers, :permissions,
+                                    workshop_host: :sponsor,
+                                    chapter: { permissions: :members })
                         .where(id: grouped['Workshop'])
                         .to_a.index_by(&:id)
     meetings = Meeting.eager_load(:venue, :organisers, :permissions).where(id: grouped['Meeting'])

app/presenters/workshop_presenter.rb

@@ -127,6 +127,6 @@ def map_member_details(organisers, member, role)
   end
 
   def chapter_organisers
-    model.chapter.permissions.find_by(name: 'organiser')&.members || []
+    model.chapter.permissions.to_a.find { |permission| permission.name == 'organiser' }&.members || []
   end
 end

spec/requests/event_card_render_query_cost_spec.rb

@@ -35,6 +35,25 @@ def count_queries
     expect(four_cards).to be <= one_card + 8
   end
 
+  it 'does not add per-card queries for hosted workshops on /events/upcoming' do
+    chapter = Fabricate(:chapter, active: true)
+    host_sponsor = Fabricate(:sponsor)
+    first_workshop = Fabricate(:workshop_no_sponsor, chapter:)
+    Fabricate(:workshop_sponsor, workshop: first_workshop, sponsor: host_sponsor, host: true)
+
+    get '/events/upcoming'
+    one_card = count_queries { get '/events/upcoming' }
+
+    3.times do
+      workshop = Fabricate(:workshop_no_sponsor, chapter:)
+      Fabricate(:workshop_sponsor, workshop:, sponsor: host_sponsor, host: true)
+    end
+
+    four_cards = count_queries { get '/events/upcoming' }
+
+    expect(four_cards).to eq(one_card)
+  end
+
   it 'does not add per-card queries on the chapter page as cards grow' do
     chapter = Fabricate(:chapter, active: true)
     organiser = Fabricate(:member)